Method of manufacturing centrifuge buckets



1934- s. R. BERGMAN METHOD OF MANUFACTURING CENTRIFUGE BUCKETS Original Filed July 13, 1932 -Fig.4.

Inventor COTTQN COVL'RED STSCL WIRE Patented Nov. 6, 1934 UNITED STATES PATENT OFFICE METHOD OF CENTRIFUG Sven R. Bergman, Nahant,

ectric Company General El New York Original application Ju 622,272. Divided and 24, 1933, Serial 4 Claims.

which it is subjected.

For a consideration novel an the folio 'onal view of a 5 is a detailed view.

Fig. 4, wh

Fig. completed bucket, and. Fig. Referring to the drawin ous wire extending from Wall 1.

The bucket is con sisting moldable material. rial, I utilize preferably spi structed from an acid re- As a moldable matennable textile fibres,

by an artificial resin such as a phenolic condensation product. The side walls may be con- MANUFACTURING E BUCKETS Mass., assignor to a corporation of ly 13, 1932, Serial No, this application October resisting and forms a covering which protects the cotton fibres from the acid.

To protect the wire from the acid and to form a bond between it and the side wall 1, I utilize wire provided with a Wrapping 7 8. After the wrapping of the wire is completed, the end is positioned in the lower groove 11 as shown in Fig. 3. I next place a suitable amount of molding material in the grooves 10 and 11 so as to cover the ends of the wire, after which, the structure is placed in a suitable mold (which may be the mold used in making the preform) and the moldable material is cured under heat and pressure. The method of molding material of this type is well known in the art and requires no detailed description. When finished, the bucket is smooth on the outside and the steel wire is completely protected by the acid resisting covering.

It is important that a bucket of this type be as smooth on the outside as possible and to improve the bucket in this respect, I may provide on the outside of the bucket a special wrapping of thin woven cloth such as thin tape. For example, I have found cotton tape of a thickness of the order of 0.007 of an inch satisfactory. The tape is first treated with the adhesive, such as an artificial resin, after which it is wound on the outside of the bucket, successive turns overlapping, it being applied after the wire is wound on and before the final molding operation. The tape in process of being wound, is indicated at 12 in Fig. 3, it being wound so that successive layers overlap about one-half their width. The bucket is then given the final molding operation and when completed, the tape provides a thin integral covering which is very smooth on the outer surface. In the finished bucket, Fig. 4, the tape covering is indicated at 13.

In connection with my improved construction, it is to be noted that the reinforcing wire is not embedded in the body of the bucket but is wound on the outer surface thereof. This is an important consideration because by locating the wire on the surface, the maximum reinforcing effect is obtained. The winding of the wire on the outer surface is made possible by reason of the fact that the wire is covered with the acid resisting coating and, as pointed out above, the fact that this acid resisting coating adheres to the material of the side wall adds greatly to the reliability of the structure since if one or more turns of wire become broken, the other turns are not affected and the strength of the structure is not appreciably decreased.

What I claim as new and desire to secure by Letters Patent of the United States, is,-

l. The method of manufacturing a centrifuge bucket which comprises making a preform from moldable material, winding successive turns of metal covered with acid resisting material on the preform, winding thin tape on the preform over the metal, and molding the structure thus formed under heat and pressure.

2. The method of manufacturing a centrifuge bucket which comprises making a preform from spinnable fibres treated with an artificial resin, winding successive turns of wire on the outer surface of the preform, the wire being covered with spinnable fibres and an artificial resin, winding thin tape treated with artificial resin over the wire, and molding the structure thus formed under heat and pressure.

3. The method of manufacturing a centrifuge bucket which comprises making a preform from moldable material, winding successive turns of metal covered with an acid resisting material on the preform, the preform over the metal. and molding the structure thus formed under heat and pressure.

4. The method of manufacturing a centrifuge bucket which comprises making a preform from spinnable fibres treated with an artificial resin, winding successive turns of metal on the outer surface of the preform, the metal being covered with spinnable fibres and an artificial resin, placing a surface covering comprising material treated with an artificial resin over the metal, and molding the structure thus formed under heat and pressure.

SVEN R. BERGMAN.

placing a surface covering on 

